Starship Asterisk*

Anthony Barreiro wrote:On the far side of the Moon there are a lot of craters with extensive bright ray patterns. On the nearside only Tycho has such an impressive set of rays. I assume that's because there's more bright highland material on the far side. Perhaps Copernicus would have longer and brighter rays if the meteoroid had hit a highland area rather than a dark mare.

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Anthony Barreiro wrote:(Is anybody still reading comments on this apod? ... .)

Anthony Barreiro wrote:

Anthony Barreiro wrote:(Is anybody still reading comments on this apod? ... .)

I guess not!

ta152h0 wrote:as a matter of fact I had an interesting conversation with a 12 yeard old recently when we drive my truck around ( I have his full attention with no external interruptions _). We talk astronomy and science in general and I mentioned mysteries that scientists have been challenged to explain. I told him one of these mysteries is why we have animals that have enough poison to kill many elephants when it appears not to be necessary. Perhaps unintentionally Jeremy opened a giant door and said it is to kill dinosaurs. First thing that came to mind is perhaps these particular animals survived the great extinction event and have been around for a really long time and not changed since the dinosaur era.

geckzilla wrote:

ta152h0 wrote:as a matter of fact I had an interesting conversation with a 12 yeard old recently when we drive my truck around ( I have his full attention with no external interruptions _). We talk astronomy and science in general and I mentioned mysteries that scientists have been challenged to explain. I told him one of these mysteries is why we have animals that have enough poison to kill many elephants when it appears not to be necessary. Perhaps unintentionally Jeremy opened a giant door and said it is to kill dinosaurs. First thing that came to mind is perhaps these particular animals survived the great extinction event and have been around for a really long time and not changed since the dinosaur era.

It doesn't sound like that much of a mystery to me. You wouldn't want to run out of poison to kill your prey if you needed to defend yourself or needed dinner for the night.

ta152h0 wrote:so contrary to some popular beliefs, people do read this stuff

ta152h0 wrote:
so contrary to some popular beliefs, people do read this stuff

neufer wrote:

ta152h0 wrote:
so contrary to some popular beliefs, people do read this stuff

People....maybe.

Time travelers... not so much.

neufer wrote:

ta152h0 wrote:
This morning I read this

http://www.nasa.gov/content/calm-skies- ... ee-oceans/

in conjunction with spaceweather.com noticing the sun is, and has been quiet for a while. Are the two connected ?

Polar stratospheric "weather" is somewhat affected by high solar activity (; e.g., by hastening the collapse of the Antarctic ozone hole each November/December).

However, tropical tropospheric weather is not

APOD Robot wrote:
In a few months, the Chinese Chang'e 3 is scheduled to launch, a mission that includes a soft lander that will dispatch a robotic rover.

http://astrobob.areavoices.com/2013/12/01/change-3-rabbit-rover-moon-bound-after-todays-successful-launch/ wrote:

Click to play embedded YouTube video.

Chang’e 3 rabbit rover’s successful launch
Astrobob, December 1, 2013

<<In Chinese folklore, the familiar spots Westerners see as the face of the man in the moon instead outline Yutu the Jade Rabbit. A robotic version of Yutu successfully launched to the moon today at 11:30 a.m. CST (1:30 a.m. Dec. 2 China time). The mission, named Chang’e-3 after the female Chinese moon goddess, marks China’s first attempt at landing a probe on another world. If successful, it will be the first soft-landing on the moon since the 1976 Russian Luna-24 sample return mission. The Chinese moon rover “Jade Rabbit” will explore the moon for at least 3 months after landing on Dec. 14. The rover will be equipped with a camera, an instrument to determine the chemical element composition of lunar rocks and a radar device on its underside to measure lunar soil depths.

[b][color=#0000FF]The lander will touch down in a picturesque part of the moon called Sinus Iridium or Bay of Rainbows near the crater Laplace A. The bay, a 160-mile-wide lava-flooded, relic crater, is easily visible in a pair of binoculars from waxing gibbous through last quarter phase. Credit: John Chumack (left) and NASA.[/color][/b]

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[b][color=#0000FF]After landing, the rover will “walk” down a ramp from the lander to explore the moon. Its six wheels can be steered individually much like NASA’s Curiosity.[/color][/b]

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After setting down near the 9 km-wide crater Laplace A in the Bay of Rainbows or Sinus Iridium on Dec. 14, the 120 kg rover will roll of a the lander’s ramp and onto the lunar surface. Powered by solar cells, Yutu is expected to operate for at least 3 months and explore within a 5 km radius of the lander. Meanwhile the lander will serve as a stationary science station and run off electricity generated by Radioisotope Thermoelectric Generators (RTGs). RTGs convert the heat radiated by the decay of plutonium-238 into electricity.

The lander is equipped with seven instruments and cameras for studying the lunar environment. The main instrument is a telescope for viewing the sky in near-ultraviolet light. With no atmosphere to filter UV out, scientists will photograph galaxies, stars and the Earth.

It’s only a hope, but wouldn’t it be nice if mission control uses either the rover or lander cameras to make a few time exposures of the perpetually dark lunar sky, preferably with the Earth in the frame. As long as we’re there, wouldn’t you like to see our planet’s globe suspended among the stars of another world?

While the Apollo astronauts photographed the Earth from the moon’s surface, they only captured the bright planet, not the stars. To do that would have required a time exposure and tripod, a task (and equipment) not on their list of a million things to do in the short time they spent on the moon.

Jade Rabbit will also use its alpha particle X-ray spectrometer on a robotic arm to zap lunar rocks with alpha particles (helium nuclei) and X-rays and measure what’s scattered back to determine their elemental composition. It will also take pictures, shoot real-time video and carries a ground-penetrating radar device in its belly for measuring lunar soil depths down to 30 m and moon’s rocky crust to 300 m.

Yutu can explore on its own but will be controlled and guided from Earth when necessary. The Chang’e-3 mission was preceded by the Chang’e 1 and 2 lunar orbiters and will be followed by a sample return flight and ultimately by a manned moon landing of taikonauts, the Chinese word for astronauts from the Cantonese ‘taikon’ or cosmos.>>

http://astrobob.areavoices.com/2013/12/13/change-3-lunar-rover-ready-for-daring-moon-landing-saturday/ wrote:
Chang’e 3 lunar rover ready for daring moon landing Saturday
Astrobob December 13, 2013

[b][color=#0000FF]Chang’e 3 lowers its orbit from a 62-mile circle to elliptical with the low point of 9.3 miles over the Bay of Rainbows. Credit: CNSA[/color][/b]

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Click to play embedded YouTube video.

<<China’s Chang’e 3 lander will begin its descent to moon’s surface at 7:10 a.m. (CST) tomorrow Dec. 14. In an era when it takes months and years to arrive at places like Mars and Jupiter, it’s almost shocking that the Chinese mission, launched less than two weeks ago, will soon touch lunar soil.

Of course, the moon’s so much closer than any planet, it’s a no-brainer to get there in a hurry, but it’s been so long since we’ve visited the place, it makes me wonder why we haven’t considered putting rovers up there sooner and as routinely as we send them whizzing off to Mars.

Few would deny Mars is a bigger, juicier target than old Luna. Naturally, it comes down to money. With only so much, you have to pick and choose your missions. That’s why I get a kick whenever a new country joins the space exploration race. I don’t care if it’s national pride, testing of technology or whatever. Just shoot the probe up there and get some science done. Oh, and don’t forget to send us a postcard. Preferably every day.

I shouldn’t complain too much about the lack of recent moon missions. NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE) safely arrived in lunar orbit in October and the next month starting sniffing out lunar argon, potassium and sodium and recording moon dust even at high altitudes. But there’s nothing like a rover to make you feel like you’re right there clomping around on the ground.

We humans have an insatiable appetite for new worlds. Ever since our ancestors left Africa some 100,000 years ago, we’ve wondered what’s around the next bend. Next November the European Rosetta probe will deploy a tiny robot to land on Comet 67P/Churyumov-Gerasimenko; in July 2015 New Horizons will fly by Pluto and its handful of moons. Bring it on!

On Dec. 10, mission control at the Chinese National Space Agency (CNSA) fired thrusters on Chang’e 3 to change its 62-mile-high circular orbit to an elliptical one with a low point 9.3 miles (15 km) high over the landing target in the Bay of Rainbows. Rocket engines will fire again a final time Saturday at 7:10 a.m. 10 minutes later, the craft will make a soft landing on the moon.

To prevent it from smashing into rocks on the way down, the lander’s equipped with terrain recognition equipment to help it automatically avoid obstacles like the boulders Neil Armstrong had to steer the Apollo 11 craft around before he and Buzz Aldrin made their historic touchdown on July 20, 1969.

Assuming a trouble-free landing, the rover, nicknamed “Yutu” or Jade Rabbit, will roll down from the lander on a ramp and onto the surface. Both probes will run on solar energy during the 2 week long lunar day; during the equally long night, when temperatures can drop to -280 F (-173 C), radioisotope heater units will keep them warm enough to operate even in the deep chill.

Three panoramic cameras facing different directions and one descent camera outfit the lander, while the rover boasts two panoramic cameras, two navigation cameras and two hazard avoidance cameras (much like the Mars Curiosity Rover). Naturally, the moon itself will be the No. 1 science target, but scientists will also take pictures of celestial objects in the lunar sky and study everything from distant galaxies to Earth’s plasmasphere with a 6-inch (150mm) telescope sensitive to ultraviolet light.

I’ll have an update and maybe even early photos come tomorrow. We wish the Chinese the best. I can’t wait!>>

Chang'e 3's landing on the Moon is now scheduled to begin at 21:40 Beijing time on December 14, which is 13:40 UT or 05:40 PT. That's about two hours earlier than previously stated. Once deceleration begins, the whole process will take about 750 seconds.